Abigail hides from a Mook behind a butcher's counter. The butcher first tells her that she has to leave, but she says she's hiding from her ex-husband, gesturing to the large, muscular man. The butcher tells her she can stay as long as she wants (which got her dubbed "da real mvp" in the Tumblr fandom, especially by those who have experience with domestic abuse).
It's a rather small, blink-and-you'll-miss monent. Just as the group finds the treasure, Ben and his dad share a hug. Especially moving when one considers they were at each other's throats when Ben first arrived at his house, this is a moment for any people on the outs with their parents to maybe push them towards reconnection.
Before that, when they found the fake room and Ben sinks into a Heroic B.S.O.D.. First Patrick, then Abigail step in to help him out of his funk.
Ben: (distraught) I just... really thought I was gonna find the treasure.
Patrick: Okay. Then we just keep looking for it.
Abigail: I'm in.
And when Ben tells his dad that he was right about the treasure being a wild goose chase, Patrick responds with "No, Ben, you were right. This room is real, and that means the treasure is real. We're in the company of some of the greatest minds in history because you found the clues they left and understood their meaning. And I've never been so happy to be proven wrong."
After God only knows how many years, and probably decades because he's already long since become disillusioned by the time we hear of it from his father (played admirably by Christopher Plummer), of his father pissing on the idea of the treasure being real, to hear his dad admit he was actually wrong is probably what really snapped him out of his funk.
The mere fact that the "National Treasure" of the title isn't gold or jewels but history — scrolls from Alexandria and statues from Egypt, precious treasure of civilization thought lost during the Dark Ages...holy cow, man.
In National Treasure 2 - Riley, when trying to convince the rest of the treasure hunters to trust him on the President Secret Book myth:
Riley: "Ben, if it was you trying to convince me...you'd have less evidence and I would already believe you."
Mr. and Mrs. Gates' reconciliation.
Riley meeting a cute girl who actually read his book, and is an actually fan of his (not just somebody mistaking him for Ben).
Cute Girl: I recognize you from your book. Will you sign it?